Association between scale-free brain dynamics and behavioral perfo rmance –Functional MRI study in resting state and face processing task

学位記番号：医博甲1672

Angular analysis of bremsstrahlung in alpha decay

A new quantum electrodynamical method of calculations of bremsstrahlung spectra in the $\alpha$-decay of heavy nuclei taking into account the angle between the directions of $\alpha$-particle motion (or its tunneling) and photon emission is presented. The angular bremsstrahlung spectra for $^{210}{Po}$ have been obtained for the first time. According to calculations, the bremsstrahlung in the $\alpha$-decay of this nucleus depends extremely weakly on the angle. Taking into account nuclear forces, such dependence is not changed visibly. An analytical formula of the angular dependence of the bremsstrahlung spectra is proposed and gives its harmonic behavior. The extremal values of the angle, at which the bremsstrahlung has maximal and minimal values, has been found.Comment: 15 pages, 1 file of figure in EPS format, LaTeX v.2e with EPJ style. In the new variant of the paper: 1) more attention is given to a convergence problem of computer calculations of the bremsstrahlung spectra; 2) a new section with inclusion of Woods-Saxon component in construction of the total realistic $\alpha$-nucleus potential into our model (with our first brermsstrahlung spectra for $^{210}{Po}$ at such potential) is included into the paper; 3) possible ways of further improvement of the quantum-mechanical models are pointed ou

Money versus Time: Evaluation of Flow Control in Terms of Energy Consumption and Convenience

Flow control with the goal of reducing the skin friction drag on the fluid-solid interface is an active fundamental research area, motivated by its potential for significant energy savings and reduced emissions in the transport sector. Customarily, the performance of drag reduction techniques in internal flows is evaluated under two alternative flow conditions, i.e. at constant mass flow rate or constant pressure gradient. Successful control leads to reduction of drag and pumping power within the former approach, whereas the latter leads to an increase of the mass flow rate and pumping power. In practical applications, however, money and time define the flow control challenge: a compromise between the energy expenditure (money) and the corresponding convenience (flow rate) achieved with that amount of energy has to be reached so as to accomplish a goal which in general depends on the specific application. Based on this idea, we derive two dimensionless parameters which quantify the total energy consumption and the required time (convenience) for transporting a given volume of fluid through a given duct. Performances of existing drag reduction strategies as well as the influence of wall roughness are re-evaluated within the present framework; how to achieve the (application-dependent) optimum balance between energy consumption and convenience is addressed. It is also shown that these considerations can be extended to external flows

New measurement of screening potential by 'cooperative colliding process' for the d+d reaction in metallic electron environment

This is a slide-show to accompany the oral presentation by J. Kasagi entitled: "New measurement of screening potential by 'cooperative colliding process' for the d+d reaction in metallic electron environment"

Variations in floral traits of sympatric alpine shrubs, Phyllodoce caerulea and Phyllodoce aleutica, along snowmelt gradients

Floral traits (corolla length, corolla shape, anther-stigma distance, and corolla color) of sympatric alpine shrubs, Phyllodoce caerulea and Phyllodoce aleutica, were compared among three populations having different snowmelt timing selected along snowmelt gradients (i. e., early-, middle-, and late-snowmelt population) at three snowbeds in the Taisetsu Mountains, northern Japan. The corolla of P. caerulea was longer and more oblong than that of P. aleutica. The anther-stigma distance of P. caerulea was longer than that of P. aleutica. These morphological differences suggest that flowers of P. caerulea are more suitable for outcrossing than those of P. aleutica. The anther-stigma distance of P. aleutica tended to increase in the late-snowmelt populations. This supports our previous results that P. aleutica increased outcrossing success but decreased selfing ability by autodeposition in late-snowmelt populations. The corolla color of both species varied considerably among populations within each snowbed, however, directional trends in changing patterns were not detected along the snowmelt gradients. Coefficients of variation in corolla length, corolla shape, and anther-stigma distance did not show any directional patterns along the snowmelt gradients in either species. Although clear directional trends in most floral traits were not detected along the snowmelt gradients, these traits were more variable among populations within each site than among sites in both species. Thus, differences in snowmelt timing may be an important factor maintaining genetic variations within a local area